As I've gotten older, and am more and more confined to my apartment by a chronic illness, I've taken to wearing sweatpants around the house, because they are warm and comfortable.
But none of my sweatpants have a fly. And sometimes I wear them underneath roomy cargo pants, sort of like long johns. And then the lack of a fly is a real nuisance.
Before I sit down at the sewing machine and try to figure out how to add a fly to my sweatpants, I thought it might be worth a try to see if someone else had already figured it out and has a pattern they could share with me.